Parallelized Fully-Coupled Mixed Elastohydrodynamic Lubrication Analysis and Wear Prediction for Tunnel Boring Machine Main Bearings

The tunnel boring machine (TBM) main bearing operates under heavy-duty and slow-speed conditions, with lubrication performance being critical to service life. This study presents the first comprehensive analysis of lubrication at TBM main bearing contact interfaces. A parallel-computing-accelerated numerical model is established to simulate multi-body mixed elastohydrodynamic lubrication (EHL) and wear, validated against experimental data under realistic operating conditions. Lubrication and wear behaviors of axial and radial rows are evaluated under different roller profiles. Results indicate that a logarithmic profile doubles film thickness and reduces wear by 87.7% for axial rollers, while dub-off and crowned profiles increase film thickness by 1.53 times and reduce wear by 70.2% for radial rollers. The study offers insights into profile optimization for TBM bearings.